Kevlar Inventor Dies at 90

22 Jun 2014By Mike Hoffman

A woman whose search for new materials for automobile tires 50 years ago led to the accidental discovery of Kevlar died June 18 in Delaware.

Stephanie Kwolek, 90, never became a household name, but Kevlar is known worldwide and is today synonymous with body armor that has saved the lives of hundreds of American troops and thousands of police officers.

The Pennsylvania-born Kwolek went to work as a chemist for DuPont after graduating from Margaret Morrison Carnegie College, the woman’s college of Carnegie-Mellon University. She was conducting experiments on new, strong, heat-resistant materials that the company hoped to market to automakers when one of her mixes took a turn for the strange: the synthetic chemicals she was putting into a solvent turned into a liquid crystal.

“This would be as if you kept on adding flour [to a liquid] and it got thicker and thicker, until suddenly it got thin again – which was completely unexpected – and this was because the polymer had turned into a liquid crystal,” Michal [sic] Mayer, editor-in-chief of Chemical Heritage magazine told NBC’s Richard Engel for an episode of the National Science Foundation’s “Chance Discoveries” series.

That was in 1965. By the early ‘70s Kevlar – a spun fiber that was stronger than steel – was being mass produced and finding its way into far more than tires. By the mid-70s it was replacing nylon in bullet-proof vests.

Kwolek has been remembered within the military. In recent years she has been among those featured during Defense Department observances of Women’s History Month. At F.E. Warren Air Force Base, Wyoming in 2011 her contribution to saving lives of service members was recalled during a luncheon where Air Force women portrayed historical figures.

The number of law enforcement officers whose lives have been saved by Kevlar vests have been put between 2,000 and 3,000. Officials say the vests have saved hundreds of troops over the last dozen years of war in Iraq and Afghanistan.

Kwolek, in an interview with USA Today in 2003, said: “Not in a thousand years did I think the discovery of this liquid solution would save thousands of lives. When I watch the war on TV, I take great pride in saying, ‘We at DuPont invented that.’ ”